1. Field of the Invention
The present invention relates to a nonwoven fabric, a hygroscopic member, a method and an apparatus for producing a nonwoven fabric and an organic electroluminescence display with a nonwoven fabric serving as a hygroscopic member for absorbing moisture.
2. Description of the Related Art
Now, an organic electroluminescence display used as a display of various electronic equipments has been promptly developed, and already put into practice in a certain field, such as a display for a cellular phone. Such a organic electroluminescence display of such a kind is formed by laminating a plurality of layers such as an electrode layer (anode and cathode), an electron transition layer, a positive hole transition layer and a luminescence layer on a substrate, each of these layers being made of polymeric or monomeric organic compounds. On the other hand, it has been known that the organic electroluminescence display is easily deteriorated by moisture. That is, in the organic electroluminescence display, the luminescence layer and the electrode layer are separated from each other by the existence of moisture or the molecular structure of the luminescence layer changes due to moisture to result in a display defect called a dark spot.
Accordingly, when the organic electroluminescence display is produced, it is usual that the organic compound layers are formed on the substrate while not being exposed to the atmosphere, and an assembly of the formed layers is sealed within a sealing member made of metal, resin or glass. As described in Japanese Patent Application Laid-open No. 2000-195661, a drying agent is disposed in the interior of the sealing member.
To provide the drying agent in the interior of the sealing member, however, it is necessary to attach the drying agent at a predetermined position in the interior of the sealing member after it has been put in a package or mixed with the organic compound. Accordingly, a process for producing the organic electroluminescence display becomes considerably complex accompanied with the provision of the drying agent. Also, when the drying agent is disposed within the sealing member, it may be necessary to form a mounting section for the drying agent in the sealing member, which disturbs the compactness (thinning) of the organic electroluminescence display. The present invention is directed to overcome one or more of the problems as set forth above.